DIY Files: How to Build Your Own Bed Bug Detector

Here’s an after-school science experiment gone right: researchers at Rutgers University in New Jersey created a homemade bed bug trap using a cat-food dish, an insulated jug and some dry ice pellets.

According to the lead investigator, Wan-Tien Tsai, who reported her findings last December at the annual meeting of the Entomological Society of America, the dry-ice-and-jug combo lured the bloodsucking critters in an infested apartment just as effectively as, if not better than, equipment used by professional exterminators.

The contraption consisted of an insulated one-third-gallon jug (you can find them in camping stores) filled with about 2.5 lbs. of dry ice pellets. The spout was left open, allowing carbon dioxide — the telltale sign of a breathing, blood-filled meal nearby — to seep out, enticing the nocturnal insects for some 11 hours. The setup, as described in an article on sciencenews.org:

[Tsai] stood the jug in a plastic cat food dish with a piece of paper taped on the outside of the dish as a ramp up to the rim. The bowl’s steep, slippery inside, with an added dusting of talcum powder, kept bugs from crawling out again. … The parts, including the dry ice, cost $15 and don’t require any special skills for assembly. “Everyone can do it,” she said.

The MacGyver-ized bedbug trap can’t replace a proper extermination of an infested home, but it could at least let you know whether or not you’ve got a problem. Bed bugs have made a serious comeback in North America over the past few years, especially in big cities like Toronto, San Francisco and New York, where complaints of infestations in rental apartments have increased many times over. Increasing international travel has also contributed to sharp rises in bed bug activity around the globe. The creatures don’t discriminate in the places they infest — they’ve been found in apartment buildings, hotels, dorms, schools and even subway stations.

For everything you never wanted to know about bed bugs, some further reading: a comprehensive bed bug website written by Michael Potter, an entomologist at the University of Kentucky College of Agriculture; a New York Times article about dogs that sniff out bed bugs [update: a more recent and comprehensive Times article here]; and an online registry where users report bed bug infestations in apartment buildings and hotels in North America.